Apparatus of this type are used particularly for treatment of muscular pains and include electrodes between which flows a current of piezoelectric origin.
Piezoelectric generators are also used in fields of application other than the therapeutical fields and, in particular, they are used as igniters of various devices due to their great operational security.
There is in this respect particular by known gas lighter devices which comprise in a body of plastics material a piezoelectric generator having a terminal connected to an electrode while an other terminal is connected to a conductive nipple forming, with the electrode, an air gap in which flashes a spark when the piezoelectric generator is energized.